Unsolicited, low-quality communications, often (but not necessarily) high-volume commercial solicitations, sent through a range of electronic media, including email, messaging, and social media.
Commentary:
- Dates back to 1980s BBS (Bulletin Board System, an early form of online communities) slang for repeated posting in volume to flood out rival messages, derived in turn from a Monty Python comedy sketch in which “spam” is said over a hundred times.